Clothes washing machine having a cycloidal gear case



T. R. SMITH 3,184,934

CLOTHES WASHING MACHINE HAVING A CYCLOIDAL GEAR CASE May 25, 1965 4 Sheets-Sheet 1 Filed Aug. 13, 1962 y 25, 1965 T. R. SMILI'H 3,184,934

CLOTHES WASHING MACHINE HAVING A CYCLOIDAL GEAR CASE Filed Aug. 13, 1962 4 Sheets-Sheet 2 O O o O O O O O O O O O O O O O O O O O 55 O o o o I O O O O I 4 19/ T 44 47 8.4 5755 59 35' 67 F W W %& m

May 25, 1965 r, R'. SMITH CLOTHES WASHING MACHINE HAVING A CYCLOIDAL GEAR CASE Filed Aug. 13, 1962 4 Sheets-Sheet 3 May 25', 1965 T. R. SMITH CLOTHES WASHING MACHINE HAVING A CYCLOIDAL GEAR CASE Filed Aug. 13. 1 962 4 Sheets-Sheet 4 United States Patent 3,184,934 CLOTHES WASHWG MACHINE HAVEJG A CYCLUIDAL GEAR CASE Thomas R. Smith, Newton, lowa, assignor to The Maytag Company, Newton, Iowa, a corporation of Delaware Filed Aug. 13, 1962, Ser. No. 216,667 4 Claims. (Cl. 68133) This invention relates to apparatus for treating fabrics, and more particularly to cleaning fabrics in a washing machine.

Various agitating devices have been proposed heretofore for washing machines. In a vertical axis Washing machine, the conventional agitator is oscillated in long strokes, which may be, for example, 210. The long stroke is characterized by a high-amplitude and a low frequency. The advantage of the long stroke oscillation is the turnover of the clothes in random fashion. It has been known that a short stroke, high frequency agitation gives good washing efficiency, particularly in the vicinity of the agitator.

It is, therefore, an object of the invention to provide a device for cleaning fluids with a high degree of efiiciency. It is another object of the invention to provide a device that may be used with conventional type washing machines, for example, the vertical axis type. Further objects and advantages of this invention will become evident as the description proceeds and from an examination of the accompanying drawings which illustrate a preferred embodiment of the invention and in which similar numerals refer to similar parts throughout the several views.

In the drawings:

FIGURE 1 is a side elevation, partly broken away, showing a machine of the vertical axis type incorporating the preferred embodiment of the invention;

FIGURE 2 is an enlarged fragmentary vertical sectional view of the embodiment shown in FIGURE 1, showing the transmission;

FIGURE 3 is an enlarged perspective view of the upper portion of the gear case of FIGURE 2;

FIGURE 4 is an enlarged perspective view of the upper portion of the gear case as shown in FIGURE 3 with the rack assembly removed; and

FIGURE 5 is an enlarged cross-sectional view taken substantially along line 55 of FIGURE 2.

Referring to FIGURE 1, there is shown a base frame mounted on adjustable feet 11 and provided with a supporting dome 12 rising out of a centrally located depression 13 in base frame 10. Dome 12 serves as a mounting for a drive assembly 14.

Base frame member 10 also supports the lip-ended reversible motor 15 and the water pump 16 which, like drive assembly 14, is driven by motor 15 through belt 17 on the underside of base frame 10. Pulley 18, which is driven by motor 15 through belt 17, serves as the input member for the drive assembly 14.

Cabinet 21, attached to and enclosing base frame 10 together with the drive and tub assemblies supported thereby, is provided at its upper end with 21 depending annular flange 22 defining an access opening into the washing machine apparatus which is normally covered by access door 24.

The drive assembly 14 is more fully described and shown in Goodlaxson Patent No. 2,948,372, dated August cent opening 27 the dome 12 is provided with friction tpce pads 26 at its periphery and at its uppermost portion. An umbrella-like support member 28 rests on these friction pads 26 and is provided with three equally spaced ears 29 for three centering springs 31 which are fastened to brackets 32 connected to base frame 10. This arrangement centers support member 28 on dome 12 and restrains it from rotation relative to base frame 10.

Threaded into the umbrella support member 28 is a member 34 of substantially frusto-conical configuration which serves as a housing for drive assembly 14. Housing member 34 cooperates with umbrella support member 28 by gripping the outer race of a thrust bearing 35 which is provided with a inner race. Mating with and seated in this inner race of bearing 35 is the spin tube or shaft 37 which journals a power shaft 38 also extending into the drive assembly 14. With this construction all weight placed on the spin tube 37, housing 34 and on umbrella member 28 may be used to an advantage to provide ample frictional forces between umbrella member 28 and the friction pads 26 for dampening nutational movements of the shafts 37 and 38 relative to dome 12 while permitting rotational movement of spin tube 37 in thrust bearing 35.

Upon energization of motor 15 in a direction to rotate pulley 18 in a counterclockwise direction as viewed from the bottom of FIGURE 1, power shaft 38 is rotated in this same direction While spin shaft 37 is held against rotation by appropriate braking mechanism Within housing 34. Upon the reversal of motor 15, spin shaft 37 is released for rotation to allow shafts 37 and 38 to be spun in unison in a clockwise direction. 7

With the drive and support constructions set forth above, it can be seen that shafts 37 and 38 may be selectively rotated as determined by the direction of rotation imparted to pulley 18 while permitting nutation of the umbrella-like support member about a vertical axis at all times. In the washing machine illustrated in the accompanying drawings, shafts 37 and 38 nutate on a point determined by the intersection of the vertical axis of rotation with a horizontal plane bisecting radial plane of pulley 18.

Referring now to the tub assembly, the umbrella support member 28 is provided with three recessed upstanding lugs 41 spaced equally from each other and alternately around member 28 with respect to the three cars 29. While not entirely shown in FIGURE 1, it will be apparent from this description that there are three lugs 41 spaced 126 from each other each of which is 60 removed from an adjacent ear 29. 1

Fastened within the recessed lugs 41 by connectors 4-2 are the three tub brace members 43 which are, in this embodiment, of channel-like cross section. Brace members 43 extend outwardly and upwardly from umbrella support member 28 to join the non-rotatable imperforate outer tub 44 through tub connectors 45 to form an in verted tripod support for tub 44. The tub 44 is provided with a bottom wall 47 in which is formed a C-shaped gutter 48 having its lowermost portion converging into the drain outlet 49 which in turn communicates with the water pump 16 through the flexible drain hose 51.

The non-rotatable outer tub 44- is provided with a removable crown 52 which permits removal of the rotatable inner clothes basket or receptacle 53 nested within-tub 44. Clothes basket 53 has a perforate bottom wall 54 and a perforate cylindrical side wall 55 which carries a concrete inertia ring 56 at its uppermost end. A conventional oscillating type agitator 57 is mounted within the clothes receptacle 53.to'provide the proper agitation of fabrics placed within the tub assembly thus formed. Housed by covers 58 and 59 and driven by power shaft 33 is a motion converting transmission 70. V

Spin tube 37, extending into drive assembly 14, carries at its upper end the lower gear case cover 58 which in turn is bolted to the upper gear case cover 59. Referring to FIGURE 2, the upper gear case cover 59 is provided with a mounting stem 64 extending upwardly in a coaxial relationship to spin shaft 37 with which it forms a unitary extension. Threaded on stem 64- is a tub carrier member to which is secured the bottom wall '54 of clothes basket 53. When the stem is rotated by spin tube '37 during the fluid extraction cycle, rotation of the clothes basket 53 is effected.

A sealing engagement as more fully described in Smith Patent No. 230L294, dated August 25, 1959, provides an air and water tight seal for the mounting stem 6 while permitting both rotational and slight lateral movements to take place between the clothes basket 53 and the outer tub 44.

Agitator 57 is splined to the upper end of agitator shaft 67. Shaft 67 receives its washing movements from the motion converting transmission 7t). Transmission is driven by shaft 3,8.

, Upon rotation of drive assembly pulley 18 by motor 15 in a counterclockwise direction as viewed from the bottom of FIGURE 1, spin shaft 37 will be braked by mechanism Within assembly 14 while power shaft 38 will cause agitator shaft 67 to drive agitator 57 within tub 53. Upon reversal of motor 15, pulley 18 will drive shafts $7 and 38 in unison to extractfluids from damp fabrics Within tub 53 by means of the connection existing between tub 53 and spin shaft 37.

It should be apparent that the type of1 movement trans-. mitted to shaft 67 by. transmission 70 will be imparted to the agitator 57. The. agitator 57 in turn accomplishes the washing action within basket 53.

Referring to FIGURES 2 and 5, the transmission 70 ill now be described. Power shaft 38 has an eccentric- 71 splined atits upperend. The eccentric 71 is mounted within a circular opening 72 in a cam plate 73. Opening 72 is concentric to the outer circular circumference of cam plate 73'. However, the power shaft 38 is mounted. off-center as to both eccentric 71 and cam plate .73.

A reaction plate '77 is secured to the lower cover 58. On the circumference of the cam plate 73 are eleven lobes 75 separated by recesses 76 of an epitrochoidal curve. On the inner circumference of reaction plate. 77 are twelve lobes 78 separated by recesses '79. The size of the lobes and recesses on the reaction plate 77 are designed to accommodate-the lobes and recesses on cam plate 73. 7

An eccentric pin 80 is secured off-center to cam plate 73. Pivotally mounted on pin 89 is a slide block 81. Fixed in slide block 81 is a bearing member to provide a suitable contact surface between the slide block 81 and pin 86;

Referring now to FKGURES 2 and 3, the slide block 81 is slidably mounted'in Way 82 of a rack memben83. Slide block 81 is free to transverse the entire length'of way 82 as pin 80 is rotated and moved by cam plate 73.

Rack member 83 is formed with outer shoulders, 84

and: keys 85, which engage corresponding shoulders 36 and key-ways 87 in depending bars 88, which are secured to, the upper housing cover- 59. One interior wall of rack member $15 has secured thereto rack teeth 39, which Whichare transmitted-to the agitator 57 through agitator v shaft 67. I

' The operation of the scribed." Thedrive shaft '38'is rotated by drive, assembly 14 at about 618 revolutionsper minute. The eccentric 71 secured to'the upper end of the drive shaft 38 throws the cam plate 73' ecccntrically, so that the cam plate rolls around the reaction plate 77 at reduced speeds ,of about 51.5 revolutions perminute. The resultant loci of the movements of the slide block 81 is an etpitrochoidal curve. The slide block 81 rotation isconverted by the rack member 83 to straight line movements which are imparted to the agitator 57.

One revolution of the slide block 31 about power shaft 3%; produces a-major stroke of the rack member 83, which is of a low-frequency. and high-amplitude. One revolution of the slide block 81 through a single lobe of the epitrochoidal curve, caused by the cam plate 73. walking around the inner circumference of the reaction plate 77, produces a minor stroke: on the rack member 83, which is of a high-frequency and low amplitude. The resultant movement produced on agitator 57 is a major stroke having a hi' hamplitude and a low-frequency, upon which is superimposed a minor stroke having lowamplitude and high-frequency.

The advantagesyof the inventionare unique. The random turnover of the clothes achieved by a long stroke is maintained. At the same time,,.the clothes are subjected to a low-amplitude, high-frequencypulsation. The combined effect is a high degree of Washing efiiciency.

In the drawings andspecific'ation there have been set forth several embodiments of the invention, and although specific terms are employed, these are used in a generic.

and descriptive sense only, and not for purposes of limitation. Changes in form and proportion of parts, as well as the substitution of equivalents are contemplated, as

, a power shaft member, means. for rotating said power shaft member, an agitator shaft member and transmission means including in a housing member, an eccentric member drivably connected to said power shaft member, an annular reaction plate member secured to said hous ing and having an engagement surfaceon the inner circumference thereof, a cam plate' member eccentrically driven by said eccentric member and having an outer circumference smaller than the inner circumference of said reaction plate member and disposed for engagement therewith an eccentric drive member connected to said canrplate--member, and means connecting said eccentric drive member and said agitator shaft member whereby 'movement of said eccentric. drive member eflects'said undulation and pulsationsof said agitator shaft member 2. In device for cleaning fabrics, the combination comprising: a tub member for containing a body of fluid and fabrics to be cleaned, agitator means in said tub member, means for oscillating said agitator means with relatively high-amplitude, low-frequency undulations in said body of fluid,lan'd means for simultaneously oscillating said agitator meanswith relatively low-amplitude, high 7 frequency pulsations,.said means foroscillating said agitatransmission 79 will now be detor .means with undulations and pulsations including a power'shaft member, :means for rotating said power shaft member, an agitator shaft memiber and transmission a means including in alrousingfan eccentric member drivablyconnected tosaid power shaft member, an annular reactionplate member secured tosaid housing and having an eng'agernentsurface on the inner circumference there of, a cam plate 'rnem ber, ecc'entrically driven by said eccentric member and having an outer circumference smaller than the inner circumference of said reaction plate member and disposed for engagement therewith, an eccentric drive member connected to said cam plate memher, and means connecting said eccentric drive member and said agitator shaft to oscillate said agitator means with said undulations and pulsations including a pinion member fixed to said agitator shaft member, a rack member slidably mounted in said housing and in engagement with said pinion and means drivably connecting said eccentric drive member and said rack member whereby movement of said eccentric drive member is transmitted through said rack member to effect said undulations and pulsations of said pinion and agitator shaft members.

3. In a drive mechanism for a reciprocating agitator, the combination comprising: means for generating relatively high-amplitude, low-frequency oscillations, and means for simultaneously generating relatively low-amplitude, high-frequency pulsations superimposed on said high-amplitude, low-frequency oscillations, said means for genera-ting aid oscillations and pulsations including a power shaft member, means for rotating said power shaft member, an agitator shaft member and transmission means including in a housing member, an eccentric member drivably connected to said power shaft member, an annular reaction plate member secured to said housing and having an engagement surface on the inner circumference thereof, a cam plate member eccentrically driven by said eccentric member and having an outer circumference smaller than the inner circumference of said reaction plate member and disposed for engagement therewith, an eccentric drive member connected to said cam plate member, and means connecting said eccentric drive member and said agitator shaft member to transmit movement of said eccentric drive member to effect said oscillations and pulsations of said agitator.

4. in a device for cleaning fabrics, the combination comprising: a tub for containing a body of fluid and fabrics to be cleaned, agitator means in said tub member, and means for driving said agitator means with a major stroke, and means for simultaneously driving said agitator means With a minor stroke said means for driving said agitator with a major stroke and a minor stroke including a power shaft member, means for rotating said power shaft member, an agitator shaft member for driv ing said agitator means and transmission means including in a housing member, an eccentric member drivably connected to said power shaft member, a reaction plate member secured to said housing and having an engagement surface on the inner circumference thereof, a cam plate member eccentrically driven by said eccentric member and having an outer circumference smaller than the inner circumference of said reaction plate member and disposed for engagement therewith, an eccentric drive member connected to said cam plate member, a driven member fixed to said agitator shaft member, and intermediate means drivably connecting said eccentric drive member and said driven member whereby movement of said eccentric drive member is transmitted to said agitator means to effect said major and minor strokes.

References Cited by the Examiner UNITED STATES PATENTS WALTER A. SCHEEL, Primary Examiner. 

1. IN A DEVICE FOR CLEANING FABRICS, THE COMBINATION COMPRISING: A TUB MEMBER FOR CONTAINING A BODY OF FLUID AND FABRICS TO BE CLEANED, AGITATOR MEANS IN SAID TUB MEMBER, MEANS FOR DRIVING SAID AGITATOR MEANS WITH RELATIVELY HIGH-AMPLITUDE, LOW-FREQUENCY UNDULTIONS IN SAID BODY OF FLUID, AND MEANS FOR SUPERIMPOSING ON SAID HIGH-AMPLITUDE, LOW-FREQUENCY UNDULATIONS RELATIVELY LOW-AMPLITUDE, HIGH-FREQUENCY PULSATIONS, SAID MEANS FOR DRIVING SAID AGITATOR MEANS WITH UNDULATIONS AND PULSATIONS INCLUDING A POWER SHAFT MEMBER, MEANS FOR ROTATING SAID POWER SHAFT MEMBER, AN AGITATOR SHAFT MEMBER AND TRANSMISSION MEANS INCLUDING IN A HOUSING MEMBER, AN ECCENTRIC MEMBER DRIVABLY CONNECTED TO SAID POWER SHAFT MEMBER, AN ANNULAR REACTION PLATE MEMBER SECURED TO SAID HOUSING AND HAVING AN ENGAGEMENT SURFACE ON THE INNER CIRCUMFERENCE THEREOF, A CAM PLATE MEMBER ECCENTRICALLY DRIVEN BY SAID ECCENTRIC MEMBER AND HAVING AN OUTER CIRCUMFERENCE SMALLER THAN THE INNER CIRCUMFERENCE OF SAID REACTION PLATE MEMBER AND DISPOSED FOR ENGAGEMENT 